How to sell to Costco as a home furnishing supplier
Costco doesn't have an open application or a self-serve portal. It has buyers — and once a buyer says yes, a set of EDI, packaging and delivery rules stricter than most retailers'. Here's how it works, and everything our team manages once you're in.
To sell to Costco: get in front of the right buyer with a product, a price and a pack that fit the club or Costco.com; pass the samples and the vendor setup; build EDI to Costco's own specifications and send an ASN that matches every shipment before it arrives; pack and palletize exactly as the buyer specified; deliver to the depot on the appointment; and reconcile every payment for deductions. Or hand all of it to a team that has done it.
If you already sell to Costco, you know the list
The buyer — who is the portal, the onboarding, the compliance contact and the relationship, all in one person. Samples. The club-pack configuration and pallet build the buyer specified, which is not negotiable. Vendor setup and your vendor number. EDI to Costco's proprietary mapping — 850, 855, 856, 810, 997 — with the ASN driving depot receiving. GS1 labels on every carton and pallet. Depot delivery appointments by region. For Costco.com: a separate drop-ship agreement with its own standard terms, insurance requirements, packaging that survives parcel handling, and traceability rules. Deductions for every miss, and a buyer who notices.
Every one of those is a place to lose margin or lose the program. Our team runs all of them for home furnishing suppliers. You keep the buyer relationship; we do the work behind it.
How selling to Costco actually works
There are two Costco businesses. The warehouses buy on purchase orders in club packs, delivered to regional depots on appointment; assortment is small and rotates, so a placement is a program, not a permanent listing. Costco.com runs separately, largely on drop-ship: Costco.com sells the item, sends you the order, and you ship to the member under Costco.com's drop-ship terms. Both start with a buyer, both require EDI to Costco's own specifications, and both hold suppliers to shipment accuracy that setups built for other retailers routinely fail.
Three things decide your success: whether the product, pack and price fit what the buyer is building; whether every shipment matches its ASN and arrives on its appointment; and whether you keep the buyer informed before a problem becomes a deduction.
Everything we manage for you on Costco
Getting in and getting set up
- Positioning your line for the right buyer and region — product, price, club-pack configuration, sample preparation and follow-up
- Vendor setup and documentation, insurance certificates, the Costco.com drop-ship agreement and its standard terms
- EDI onboarding and testing to Costco's specifications — 850, 855, 856, 810, 997 — with full shipment hierarchy mapping
- GS1 setup: UPCs, GTINs, case and pallet labels
Item data and content
- Item setup to the buyer's and Costco.com's spec: attributes, dimensions and weights at every pack level, materials, assembly and care, compliance documents
- Costco.com content — titles, features, descriptions, images to spec, video where supported
- New items and program changes managed cleanly with the buyer
Purchase orders, shipping and inventory
- Warehouse POs acknowledged and built exactly to the specified club pack and pallet configuration; depot delivery appointments booked and kept
- ASN (856) transmitted before the shipment arrives and matching it exactly — the document Costco uses to schedule receiving
- Costco.com drop-ship orders fulfilled inside the required window with parcel-ready packaging and tracking; inventory kept accurate so the item stays sellable
- Traceability and lot documentation maintained where Costco requires it
Getting paid
- Every payment reconciled — deductions identified and matched to the PO and invoice; wrong deductions disputed with proof; short and missing payments chased
Returns and claims
- Member returns and damage claims handled to Costco's rules; return rate watched by item so a problem is fixed before the buyer flags it
Growing sales on Costco
- Sell-through and program performance reviewed with the buyer; next-program and new-item pitches prepared; seasonal and regional opportunities tracked
- Buyer relationships — 20+ years selling home furnishings into the majors
- One login on our platform to see what sold, what's live, and what we fixed
Why suppliers lose money on Costco
- 1
The pack is wrong. Costco specifies the club pack and pallet; deviate and the load is refused or deducted.
- 2
The ASN doesn't match. Costco schedules receiving from it; a mismatch stalls the depot and costs you.
- 3
EDI built for another retailer. Costco's mapping is its own; setups that pass elsewhere fail Costco's testing.
- 4
Costco.com packaging fails in transit. Parcel damage becomes returns, deductions and a buyer conversation.
- 5
Nobody talks to the buyer. At Costco the buyer is the system; silence reads as a problem.
Proof
- $100M+ in online sales managed and helped produce across Costco, Home Depot, Wayfair and the other majors — 20+ years
- 25+ home furnishing brands
- One factory: first-ever Amazon PO of $1.2M, then $8M the next year through Direct Import — the kind of buyer-driven relationship Costco programs are built on
Frequently asked questions
How do I become a Costco vendor?
There's no open application. You reach the buying team for your category and region, present the product, price and pack, provide samples, and — if the buyer says yes — complete vendor setup, EDI testing and your first PO. We help position lines and run everything after the yes.
Is Costco.com separate from the warehouses?
Yes. Costco.com operates its own drop-ship program with its own agreement, terms and packaging requirements. A supplier can sell on Costco.com without being a warehouse supplier, and vice versa.
Does Costco require EDI?
Yes for meaningful volume — 850, 855, 856, 810 and 997 to Costco's own specifications. The ASN must arrive before the shipment and match it exactly.
What is a club pack?
The multi-unit pack configuration Costco specifies for the warehouse floor — quantity per pack, case and pallet build. It's set by the buyer and isn't negotiable once agreed.
Can Grow ECommerce run Costco for us if we already sell there?
Yes. We take over the EDI, shipment compliance, Costco.com fulfillment and deduction reconciliation, and keep your buyer informed.
Glossary
- Buyer
- Costco's category buyer; the primary contact for onboarding, orders and compliance
- Club pack
- the multi-unit pack and pallet configuration Costco specifies
- Depot
- Costco's regional receiving warehouse for warehouse-program shipments
- Costco.com drop ship
- the separate program where suppliers ship Costco.com orders to members
- 850 / 855 / 856 / 810 / 997
- purchase order, acknowledgment, ship notice, invoice and functional acknowledgment EDI documents
- ASN
- advance ship notice; Costco schedules depot receiving from it
- Web ready / web complete
- GEC's terms: content set complete / live on every assigned retailer
Ready to take a line to Costco — or to run the account you already have?
Book a call. We'll tell you what the buyer will need to see, or take over the work behind the program you already have.